Thread Subject: segmentation ideas

Hi,
I'm searching for inspiration for a segmentation problem.
I have a grayscale image with an irregular shaped object of level darkish grey. This is surrounded by a darker layer, then a brighter layer (rather like an onion with a large centre) surrounded by touching objects of varying intensity.
I want to segment out the brighter layer. I can define an intensity range for the layer, but some of the other objects may be in this range. Can anyone suggest which tools I could explore for this?
Many thanks
Lindsey

"Linds " <lindsey.crowe_removethis_@talk21.com> wrote in message <he6d5f$spj$1@fred.mathworks.com>...
> Hi,
> I'm searching for inspiration for a segmentation problem.
> I have a grayscale image with an irregular shaped object of level darkish grey. This is surrounded by a darker layer, then a brighter layer (rather like an onion with a large centre) surrounded by touching objects of varying intensity.
> I want to segment out the brighter layer. I can define an intensity range for the layer, but some of the other objects may be in this range. Can anyone suggest which tools I could explore for this?
> Many thanks
> Lindsey

If you have the Image Processing Toolbox, you can just use bwlabel()

On Nov 20, 10:38 am, "Linds " <lindsey.crowe_removeth...@talk21.com>
wrote:
> Hi,
> I'm searching for inspiration for a segmentation problem.
> I have a grayscale image with an irregular shaped object of level darkish grey.  This is surrounded by a darker layer, then a brighter layer (rather like an onion with a large centre) surrounded by touching objects of varying intensity.
> I want to segment out the brighter layer.  I can define an intensity range for the layer, but some of the other objects may be in this range.  Can anyone suggest which tools I could explore for this?
> Many thanks
> Lindsey

-------------------------------------------------------------------------------------------------
Thresholding. Hole filling. To separate touching objects, you can
use marker controlled watershed segmentation (there's a MATLAB demo
for that).
Why don't you post the image somewhere so we can see it, and maybe try
something.

Thanks for the replies, I looked at the watershed demo after posting, it looks promising. Sorry also for the delay in thanks...my notify doesn't seem to be working, perhaps it is getting eaten up by an overactive spam filter.
  


ImageAnalyst <imageanalyst@mailinator.com> wrote in message <e84ae0c0-2404-4b6e-8e1b-5909c4680b49@d10g2000yqh.googlegroups.com>...
> On Nov 20, 10:38?am, "Linds " <lindsey.crowe_removeth...@talk21.com>
> wrote:
> > Hi,
> > I'm searching for inspiration for a segmentation problem.
> > I have a grayscale image with an irregular shaped object of level darkish grey. ?This is surrounded by a darker layer, then a brighter layer (rather like an onion with a large centre) surrounded by touching objects of varying intensity.
> > I want to segment out the brighter layer. ?I can define an intensity range for the layer, but some of the other objects may be in this range. ?Can anyone suggest which tools I could explore for this?
> > Many thanks
> > Lindsey
>
> -------------------------------------------------------------------------------------------------
> Thresholding. Hole filling. To separate touching objects, you can
> use marker controlled watershed segmentation (there's a MATLAB demo
> for that).
> Why don't you post the image somewhere so we can see it, and maybe try
> something.